1. Field of the Invention
The present invention relates to a flexible device substrate and a manufacturing method thereof, and more particularly, to a flexible device substrate including a waterproof layer disposed on an outer surface of a flexible substrate and a manufacturing method thereof.
2. Description of the Prior Art
Flexible device substrates can be applied to various portable electronic devices, such as flexible display, electronic paper or electronic book because of having characteristics of thin thickness, light weight, flexibility and easily carry.
In traditional manufacturing method of the flexible device substrate, a releasing layer is coated on a rigid substrate first, and then, a flexible substrate is formed on the releasing layer. After the thin-film transistors are formed on the flexible substrate, the flexible substrate can be separated from the releasing layer, and the flexible device substrate is formed. However, the traditional flexible substrate is composed of plastic, so the flexible substrate has worse waterproof ability than glass. In order to prevent mist from entering the thin-film transistors from the flexible substrate, a waterproof layer is formed to cover the flexible substrate before forming the thin-film transistors. Accordingly, there is a waterproof layer disposed between the thin-film transistors formed in the following process and the flexible substrate.
However, since the releasing layer is composed of a material with adhesion and the flexible substrate completely adheres to the releasing layer, the flexible substrate is not easily separated from the releasing layer. When the flexible substrate is separated from the releasing layer, the thin-film transistors on the flexible substrate is also easily damaged by separating stress in the separating process. Or, the releasing layer cannot be separated from the flexible substrate completely, and a part of releasing layer is left on the outside of the flexible substrate, thereby causing the bad flexible device substrate.